The assignee of the present invention manufactures and deploys spacecraft for, inter alia, communications and broadcast services. Market demands for such spacecraft have imposed increasingly stringent requirements on spacecraft payloads. For example, broadband service providers desire spacecraft with increased data rate capacity at higher EIRP through each of an increased number of user spot beans operable from geosynchronous orbit altitudes in communication with small (<1 meter aperture) user terminals.
Techniques for meeting these demands are described in U.S. Pat. No. 9,153,877, entitled “HIGH EFFICIENCY MULTI-BEAM ANTENNA”, U.S. Patent Publication No. 2015-0295640, entitled “BROADBAND SATELLITE PAYLOAD ARCHITECTURE”, and U.S. patent application Ser. No. 15/438,620, entitled, “IMAGING ARRAY FED REFLECTOR”, each assigned to the assignee of the present application, the disclosures of which are incorporated by reference herein in their entirety. Such techniques provide very narrow, high efficiency, spot beams with steep roll-off at the edge of coverage.
RF autotracking (RFAT) is a technique for steering antenna reflectors mounted to a spacecraft platform to compensate for pointing disturbances experienced by the vehicle and the antenna. U.S. Pat. No. 8,179,313, entitled “Antenna Tracking Profile Estimation” assigned to the assignee of the present invention, the disclosure of which is incorporated by reference herein in its entirety, describes an RFAT system.
Improved RFAT techniques are desirable, particularly for the contemplated antenna systems characterized as providing narrow spot beams with steep roll-off at the edge of coverage.